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New Member

Dual VLAN IP Addressing

I have a VLAN that belongs to 2 different subnets e.g. 10.x.x.x and 172.x.x.x. These 2 subnets belong to 2 different NT domains and the domains are not trusted and also we do not want to go down this line. A NIC card in the VLAn has as its primary ip address - 172.x.x.x and secondary address 10.x.x.x.

The problem is that we are trying to map to deivces on either subnet using IP Addresses and it does not work.

Doing a net use to any of the 10.x.x.x ( net use \\10.x.x.x ) on any of the PCs within the VLAN does not work. even from all other vlans. Doing it to the 172.x.x.x. does work.

What can be done to make this work?

New Member

Re: Dual VLAN IP Addressing

How are you routing the layer 3 traffic between the two IP addresses?

Have you added a secondary IP address on the vlan interface?

Also, have you added the network to your routing process to allow other parts of your network access?

If you do nothing, it is like two ships in the night, they pass each other and without ever knowing about each other.

New Member

Re: Dual VLAN IP Addressing

Yes I have L3 routing in place. The 172.x.x.x is the secondary address and the 10.x.x.x is the primary address and they are both on the VLAN.

Both come up as directly connected on the show ip route on the MSFC so we can ping subnets. On a workstation in the vlan, we can ping every where, it is just the net use or mapping command that does not work.

Any further help


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